ByJohn S. McClenahen With a boost from unusually warm weather, construction spending across the U.S. in March was at a seasonally adjusted annual rate of $944.1 billion, 1.5% higher than the revised February figure of $930 billion, the U.S. Commerce Department reported on May 3. The increase was "well above" the number the Commerce Department incorporated into its initial first-quarter 2004 GDP report released last week, says UBS Investment Research, New York. Spending on private construction was at a rate of $722.4 billion in March, 0.4% higher than February's revised figure of $719.3 billion. Residential construction was at a seasonally adjusted annual rate of $507.2 billion, 0.7% above February's revised rate of $503.7 billion. Public construction was at a seasonally adjusted annual rate of $221.7 billion, up 5.2% from February's rate and, notes UBS, "ending a string of weak reports."